The VOR that clicked

I was like most student pilots when I was first exposed to VOR concepts, completely disorientated and off course. I quickly learned that the first tip is to throw out all thought of TO and FROM actually meaning anything to do with where you are pointing or heading.

The next item I found somewhat helpful was a tip in Rod Machado’s Private Pilot Handbook: The Ultimate Private Pilot Book. He made it clear that it was really only useful for the exam and not practical in the real world. It was a template that you could memorize then draw out during the exam. I could see how this could be helpful but it still didn’t explain how it works enough to make sense when I’m in the air.

A simple quote from CFI Bill during ground school made it all click. He started with writing this on the board.

“If you fly heading [insert OBS heading] you will be going [TO/FROM] the VOR.”

Let’s start with this example.

VOR_example1

We are on a heading of 350 with OBS set to 030. Relatively speaking, we are definitely heading away from the VOR, but remember, we already threw out any thought of that mattering. Applying our new rule, if we were to fly a heading of 030 (OBS) then would we be flying toward or away from the VOR? We would be getting a bit closer so that means we should have a TO indication, which we do.

Now how about that course deviation needle? Which way would we have to turn if we wanted to intercept the 030 radial?

vor_example2-2Let’s first visualize us if we were to fly a heading of 030. We aren’t actually turning, just imagining if we did what it would look like. I added some overlays to help with the visuals. We can see that if we did turn our heading to match the OBS then the radial line of 030 would be to the right of our location, which is why the needle deflection is to the right.

These images are from the VOR simulator at luizmonteiro.com. The simulator makes it really easy to play with different scenarios as well as set the plane in motion to see how the VOR indication changes as you fly. You can even see how the wind will impact your course and experiment with wind correction angles while intercepting or tracking a radial. Why spend hundreds of dollars chasing needles when you can get your initial practice for free with some chair flying?

I still haven’t done too much VOR navigation in the air, but I’m sure this will help me on my next dead-reckoning x-country.

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